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Description: This video is the first of many on the subject of Reverse Engineering. I will try my best to go slow so that you can grasp the concepts properly. I would highly recommend that you try out all the samples yourself, as it will be the fastest way to learn. Please download the c code and the binary exe file (don't worry it's not a virus :D ) before starting with this tutorial. <br><br>In this tutorial we will understand how to use a Hex Editor to view a binary file and find useful things. For this video we have created a sample exe using the code shown below. The idea is to hide a string in the exe and use it for a password validation in the application. As everyone knows this is the most insecure form of authentication ;-) and we will use a Hex editor to crack the password by looking at strings in the binary file. <br><br>After watching this video, please download the binary and try it yourself. Hex Workshop is a good Hex editor and is the one used for the video. <br><br> <br>--------- Program Starts -----------<br><br><span style="font-weight: bold;">#include <stdio.h></span><br style="font-weight: bold;"><span style="font-weight: bold;">#include <stdlib.h></span><br style="font-weight: bold;"><span style="font-weight: bold;">#include <string.h></span><br style="font-weight: bold;"><span style="font-weight: bold;"> </span><br style="font-weight: bold;"><span style="font-weight: bold;">#define password "FindMeIfYouCan"</span><br style="font-weight: bold;"><br style="font-weight: bold;"><span style="font-weight: bold;">int main(int argc, char *argv[])</span><br style="font-weight: bold;"><span style="font-weight: bold;">{</span><br style="font-weight: bold;"><span style="font-weight: bold;">  char pass[100];</span><br style="font-weight: bold;"><span style="font-weight: bold;">  </span><br style="font-weight: bold;"><span style="font-weight: bold;">  </span><br style="font-weight: bold;"><span style="font-weight: bold;">  printf("Please enter your password\n\n");</span><br style="font-weight: bold;"><span style="font-weight: bold;">  scanf("%s", pass);</span><br style="font-weight: bold;"><span style="font-weight: bold;">  if ( strcmp(pass, password) == 0 )</span><br style="font-weight: bold;"><span style="font-weight: bold;">  {</span><br style="font-weight: bold;"><span style="font-weight: bold;">       printf("Congrats!! Correct Pass\n\n");</span><br style="font-weight: bold;"><span style="font-weight: bold;">  }</span><br style="font-weight: bold;"><span style="font-weight: bold;">  else</span><br style="font-weight: bold;"><span style="font-weight: bold;">  {</span><br style="font-weight: bold;"><span style="font-weight: bold;">      printf("Wrong Pass\n\n");</span><br style="font-weight: bold;"><span style="font-weight: bold;">  }</span><br style="font-weight: bold;"><span style="font-weight: bold;">       </span><br style="font-weight: bold;"><span style="font-weight: bold;">  system("PAUSE");    </span><br style="font-weight: bold;"><span style="font-weight: bold;">  return 0;</span><br style="font-weight: bold;"><span style="font-weight: bold;">}</span><br><br>------------Program Ends ---------------<br><style type="text/css">body { background: #FFF; } </style>

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